Objective      To assess the effect of different doses of recombinant human growth hormone (rhGH) on the growth velocity in Chinese children w

ith idiopathic short stature (ISS).       Methods      A total of 106 ISS patients (52 males and 54 females) were enrolled in the study from 2006 to 2010

with 75 cases of Tanner stage Ⅰ and 31 of stage Ⅱ. They were divided into 3 groups according to the doses of rhGH: a low dose group (0.26 mg/kg every week)

a middle dose group (0.35 mg/kg every week) and a high dose group (0.41 mg/kg every week) with 39

23 and 44 patients

respectively. They were given rhGH by subcutaneous injection every day  for 1 to 2 years. The changes of height (Ht)

growth velocity (GV)

height standard deviation score (HtSDS)

bone age(BA)

predicted adult height (PAH) and side effects were recorded.       Results      (1) The GV of 3 groups after 1 year treatment was enhanced to 8.22±1.93

9.97±1.95 and 11.48±1.63 cm

respectively

versus 4.59±1.45 cm

3.65±1.81 cm and 4.5±0.67 cm

respectively before treatment (

P

0.01). The high dose group gained higher GV than the low and middle dose groups (

P

0.01). As for the GV of the 3 groups after 2 years

there was no statistically significant difference (

P

0.05). (2) The bone age progress of the 3 groups after 1 and 2 years’ treatment showed no statistically significant difference (

P

0.05). (3) After 3 months of treatment

6 cases of the high dose group had mild high fasting blood glucose with 5.7

6.0

6.0

5.9

5.6

and 6.0 mmol/L

respectively

but came back to normal level after short period of stopping rhGH. Knee pain occurred in occasional individuals without bone and biochemical abnormalities.       Conclusion      RhGH has a great effect on growth for ISS

with obvious short-term catch-up growth in a dose-dependent manner. Short-term treatment does not affect the growth potential. Occasional side effects are relatively more common in high dose groups. Long term follow-up is needed.